Every geologist remembers their first day of mapping: the compass that would not agree with the outcrop, the notebook page ruined by rain, the moment a contact “clicked” into place after an hour of staring at the same cliff. What…
Coordinates are often embedded in the sgy file. However, the header doesn’t contain any details about the coordinate system. By chance, you know where the seismic profile is, or you have a map displaying GPS coordinates. Let’s use QGIS !…
Sometimes I need to check bathymetric or topographic data. A good and fast way to do it is to use SURFER. XYZ data need to be gridded first. Click Grid–>Data and open the file. Select the file you want to…
In Excel, the maximum worksheet size is 1048576 rows by 16384 columns. It means that large files, typically gridded files are hard to manipulate. https://support.microsoft.com/en-us/office/excel-specifications-and-limits-1672b34d-7043-467e-8e27-269d656771c3 A possible solution is to use SURFER, particularly the worksheet. SURFER is not free and…
In some cases, you get a file with coordinates in decimal degrees. Loading these data or converting the file to UTM coordinates can be a nightmare. Don’t panic ! Here is an example of such a file: in this file,…
Geologic mapping is a highly interpretive, scientific process that can produce a range of map products for many different uses, including assessing ground-water quality and contamination risks; predicting earthquake, volcano, and landslide hazards; characterizing energy and mineral resources and their…
The main aim will be to export nav file from the seismic software (here we use kingdom) and to import it in QGIS. You could also have nav files in ASCII format (i.e. txt files: start where *** are displayed).…
You find an interesting map, for instance in an article and you want to import it in your QGIS project. The main aim will be to redraw some features (points, lines) that you need in your study (creating a structural…
Using QGIS is essential in starting a project as it will concentrate all spatial data needed for displaying or exporting in other softwares such as Kingdom or Petrel. First, you must download the latest stable version here: https://www.qgis.org/en/site/index.html QGIS has…